A leading US bank has claimed the risk of a No Deal Brexit is increasing with Theresa May's latest attempt at a Withdrawal Agreement set to be thrown out by MPs.

Investment bank JPMorgan claimed the possibility of no-deal had increased to 25 per cent from 15 per cent after studying the latest options open to the Government.

Experts based their predictions on Boris Johnson taking over as Prime Minister, followed by a General Election and then another delay to Britain's exit to the end of the year.

Theresa May speaks after the government's withdrawal agreement was voted down for the third time in the House of Commons (Image: House of Commons/PA Wire)

JPMorgan also claimed that a further extension Article 50 was possible and sharply cut the probability of an exit on the terms of Theresa May's Withdrawal Agreement to 15 per cent from 35 per cent.

The bank's Malcolm Barr, in a research note called: "Brexit: Time to be afraid, as 'no deal' probability rises", said its predictions were based on Boris Johnson entering 10 Downing Street during early September.

He said: "Boris Johnson becomes PM in early September on a 'no deal if we have to' platform.

Boris Johnson

"The EU refuses his central objective of removing the backstop from the Withdrawal Agreement. The Commons begins the process of legislating to force Johnson to seek an Article 50 extension, and Johnson calls a general election seeking a mandate for his approach.

"The UK and EU agree to extend Article 50 to end-December to allow time for the general election to take place and for discussions to follow it," the note added.

The current deadline to leave is October 31.

Theresa May will face hostile MPs as she sets out her latest Brexit plan in the Commons on Wednesday.

Her new 10-point compromise has already been dismissed by Labour, the DUP and Tory Brexiteers.

The last-ditch attempt to shore up support included offering a vote on whether to hold a second referendum, as well as a choice over the UK's future customs arrangements.